The aim of the study was to compare the efficacy and safety between sufentanil and remifentanil as an adjuvant of balanced general anesthesia.

The investigators hypothesized that sufentanil would reduce postoperative pain than remifentanil without prolonging recovery times in minor laparoscopic surgery when administered equivalent antinociceptive doses during surgery. Intraoperative opioid administration for equivalent nociception-antinociception balance could be achieved via surgical pleth index (SPI)-guided analgesia. This study was designed to compare the efficacy and safety between sufentanil and remifentanil as an adjuvant of balanced anesthesia in patients undergoing laparoscopic cholecystectomy under SPI-guided opioid administration.

Inclusion Criteria:

• Patients aged between 19 and 65 years
• Patients with American Society of Anesthesiologists physical status I or II
• Patients scheduled for elective laparoscopic cholecystectomy under balanced general anesthesia for benign cholecystic diseases
• Patients obtaining written informed consent

Exclusion Criteria:

• Patients with asthma or hypertension
• Patients with an inability to express their pain accurately
• Patients with an inability to understand the pain scale
• Patients with chronic abdominal pain or chronic pain syndrome
• Patients who required to convert to laparotomy from laparoscopic surgery
• Patients who required to receive incidental lower abdominal procedures owing to adhesion, injury, or other incidental findings at the lower abdominal cavity
• Patients with a history of drug or alcohol abuse
• Pregnant women